The local branch of Nijiya (‘rainbow shop’) Japanese supermarket in my neighborhood advertised live lobsters from Christmas Island on New Year’s Eve. I’m not sure which Christmas Island they were from (probably the one spelled Kiritimati in Kiribati, where /ti/ is pronounced [si]). The kanji string 活伊勢海老 on the poster gave me some trouble. The character 活 katsu means ‘living’, and the lobsters were indeed still alive. The characters 伊勢 ise presumably refer to Ise Bay off Ise Grand Shrine in Mie Prefecture south of Nagoya (Aichi Prefecture). And the last characters 海老 (which look like they could be read kairou ‘sea-old’) spell ebi (usually spelled in katakana エビ) ‘shrimp, prawn, lobster’, a general name for members of the order Decapoda. The more common name for 伊勢海老 Ise ebi is ロブスター robusutaa ‘lobster’.
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Joel you’re right tag reads ‘katsu ise-ebi’, live lobster. Ise-ebi is Japanese for lobster. Being old school I’d recognise it more readily than the kana for ‘robusutaa’ and I think you’d come across it more in traditional fish markets. In addition, Japanese overseas tend to stick to old school writing. When I was last in Japan a decade ago it was more common to have just the ‘ebi’ in kana.
By the way, thank you for your blog on expatriates in Meiji Japan, I’ve been helping a friend obtain information on a relative who was in Yokohama at the time.